He was taking a break from running after his six-year-old son at the playground near his home when he spotted a black pouch left unattended.
What Mr Sean Lee did not imagine was that it contained more than $10,000 in cold, hard cash.
The money was five months' worth of savings that a Chinese national working here was preparing to send home.
When Mr Lee discovered the money within an envelope stored in the pouch, the 42-year-old did the right thing. He waited for the owner to return so he could give it all back to him.
Mr Lee admitted that he was momentarily tempted to keep the money, but he realised that it "was not the right thing to do".
"The owner probably needed the money more than I did," he said.
The owner of the pouch, Mr Cui Hua Bi, was so grateful and touched by his honest deed that he told Chinese newspaper Shin Min Daily News about the incident.
Mr Lee said it was a relief when he finally handed the money over to Mr Cui last Friday, three hours after he first found it.
"I felt burdened holding on to someone else's money," said the senior business manager with a company producing dispensing systems.
He first noticed Mr Cui at about 8pm, when he was teaching his son to ride a bicycle at the foot of Block 295, Punggol Central, where they live.
Mr Cui was lying down on a bench while talking on the phone.
When Mr Lee stopped to take a break, he saw that Mr Cui had left, but a worn, black pouch was in his place on the bench.
Mr Lee opened it to find a thick yellow envelope, around $60 in cash, an ez-link card and a work permit.
"I did not open the envelope then, but when I saw the work permit and the cash in the wallet, I realised that this was someone's hard-earned money. I did not feel good keeping it," he said.
Together with his wife and son, Mr Lee waited for Mr Cui to return.
After more than an hour's wait, they went home as it was the boy's bedtime.
From his five-room flat on the 12th storey, he kept a lookout for the owner of the pouch from a window that overlooked the playground, checking every 10 to 15 minutes.
While waiting, he opened the yellow envelope and discovered nine $1,000 notes and around 30 $50 notes. There was about $10,500 in the envelope.
At around 10.45pm, Mr Lee heard worried and frantic voices coming from the playground area. Looking out his window, he saw Mr Cui searching with two friends.
He went down immediately to verify Mr Cui's identity and he recognised him as the man who had been lying on the bench earlier.
"I knew it belonged to Mr Cui because he looked like the man in the work permit photo," said Mr Lee, who also took the extra step of asking for Mr Cui's name so he could match it to the work permit.
Mr Cui, a 42-year old construction worker from Anhui province, was so grateful to Mr Lee that he thanked him "profusely over 10 minutes", calling him a good Singaporean, said Mr Lee.
At an interview with Shin Min, Mr Cui also brought grapes, apples and oranges to show his appreciation to Mr Lee.
He told Lianhe Wanbao that he realised that his wallet was missing only before he went to bed that night.
He added that while working in Singapore, he lives frugally, spending only $200 of the $2,300 he earns a month.
He was planning to send the money home, but the exchange rate was not ideal, so he decided to hold on to the money.
"When I got my pouch back, I had so many things to say to Mr Lee, but I did not know how to express my gratitude," he said.
For Mr Lee, the best reward came in the form of praise from family and friends, especially his son.
"My son told me he was going to tell his classmates about the incident," said Mr Lee.
"He said he wants to be just like me."
This article was first published on May 14, 2015.
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